56 . NORTH AMERICAN MALLOPHAGA 



be not at all surprising that parasites which come into such more intimate 

 relations with their hosts as do the blood-sucking ones (the Anoplura) as 

 compared with the hair and dermal-scale feeding ones (the Mallophaga) 

 should reveal a much more exact fitting to their host, involving structural 

 and physiological specialization. 



Although in listing in the following pages all the species of Tricho- 

 dectes so far recorded from North American mammals we have believed 

 it advisable to indicate our belief that certain species are only synonyms 

 of certain others, we have by no means attempted to make a complete 

 revision of the North American species of the genus. This undertaking 

 we may postpone until a planned attempt to make a revision of the whole 

 genus as at present known from both New World and Old World records 

 can be taken up. 



